As irresponsible as it may be to encourage drinking at this time of year, you are more likely to enjoy “A Christmas Carol: Twist Your Dickens!” at the Kirk Douglas Theatre if you toss back a few Tiny Tim-tinis or Scroogedrivers at the lobby bar beforehand. And not because your “naughtiest misdeed” — which you’ll be encouraged to write down on a slip of paper (anonymously) — might end up in the show.

It’s because the cold light of sobriety doesn’t necessarily flatter the hit-or-miss humor of this holiday confection by Chicago’s the Second City, back at the Douglas for a second year. Directed, as before, by Marc Warzecha, it features new and returning cast members, updated sketches and a fresh slate of pop-in celebrities (Rhea Perlman on opening night). But if you really want to delight in writers Peter Gwinn and Bobby Mort’s scattershot, often heavy-handed script — and to overlook the distinctly prefab feel of the improv segments — getting a little buzz on won’t hurt.

On Tom Buderwitz’s adorably Dickensian set, the likable ensemble launches into a sarcastic retelling of “A Christmas Carol,” focusing on questions that have puzzled generations such as why doesn't Marley’s ghost (Joe Liss) count himself among the three visiting spirits he announces. (“Including you?,” asks Ron West’s testy Scrooge, interrupting his chain-rattling guest. “I’m just wondering if it’s you plus three or if you’re one of the three.”)

They go on to send-up, among others, Scrooge’s nephew, Fred (Liss), who laughs continuously while sinking into insanity; the Ghost of Christmas Present (Brendan Jennings), who has a bad hangover; the silent Ghost of Christmas Future (Ithamar Enriquez), who resorts to charades and Morse code; and the plucky Tiny Tim (Amanda Blake Davis), who hosts a sleepover for three Victorian urchin friends suffering, respectively, from rickets, dropsy and “a wee case of extreme malnutrition.”

The talented cast members mock a diverse range of English accents (Jaime Moyer does a great incomprehensible cockney; Frank Caeti has perfected sweet childish piping).

But the writers, who have worked for “The Colbert Report,” apparently don’t trust that their best material will emerge from the story, as it does when Caeti keeps popping up in the house as a heckler pointing out anachronisms (and changing in and out of Leah Piehl’s charming costumes backstage at impressive speed).

Instead, they interrupt the narrative not only with bits of improv, incorporating those audience confessions, but with random skits about the three wise men, “It’s A Wonderful Life,” 1980s sitcoms, "Sister Act," and an alcoholic Rat Pack-style singer who messes up holiday classics (Jennings). They even take on “A Charlie Brown Christmas,” dressing the cast in Peanuts character cutouts and plunging them into a debate about the role of religion in public discourse. While very clever, it seems to belong in a different show.

We have enough holiday traditions that send us to the well. With ruthless pruning, “Twist Your Dickens!” just might — someday — provide a reliably funny, healthier alternative.